The invention relates to an air intake system for a commercial vehicle, in particular a truck.
DE 198 11 051 A1 shows an air intake system for an internal combustion engine, the air intake system comprising a housing for receiving an air filter. The air intake system further comprises guiding means for guiding air, the guiding means comprising at least two intake pipes. The intake pipes have different lengths, wherein closing means are provided, the closing means being configured to close at least one of the intake pipes.
It is an object of the present invention to provide an air intake system for a commercial vehicle, so that exterior noise and noise within a driver's cab of the commercial vehicle can be kept particularly low.
The invention relates to an air intake system for a commercial vehicle, in particular a truck. The air intake system comprises a hood for at least partially covering an engine compartment of the commercial vehicle. The hood has at least one frontal intake opening through which air to be guided to an engine of the commercial vehicle can flow. For example, in a completely assembled state of the commercial vehicle the engine is arranged in the engine compartment so that, for example, the engine is at least partially covered upwards in the vertical direction of the vehicle by means of the hood. The hood further has at least one plenum configured to receive the air flowing through the intake opening. This means the air flowing through the intake opening can flow into and through the plenum so as to guide the air to and into the engine which is, for example, configured as an internal combustion engine.
The air intake system according to the present invention further comprises at least one air pipe having at least one air duct with at least one inlet opening through which the air flowing through the frontal intake opening can flow so that the air flowing through the frontal intake opening can flow into the air duct via the inlet opening of the air duct. The air duct is arranged upstream of the plenum, wherein the air duct is fluidically connected with the plenum so as to guide the air to and into the plenum. In other words, the air flowing through the air duct can be guided to and into the plenum by means of the air duct. The air pipe and the hood are configured as individual components which are removably connected with each other at least indirectly. This means the air pipe and the hood are not formed in one piece, but the hood and the air pipe are separate or individual components which are removably or reversibly connected with each other. Thus, the air pipe can be mechanically connected with and disconnected from the hood without damaging the hood or the air pipe. The air intake system according to the present invention further comprises at least one air filter configured to filter the air flowing through the air duct and the plenum. Moreover, the air intake system according to the present invention further comprises at least one silencer plate arranged upstream of the air filter. Hence, the silencer plate and the air filter are different components, wherein the silencer plate is provided in addition to the air filter. Preferably, the silencer plate is rigid, i.e., inherently stable.
The silencer plate has a plurality of through openings through which the air can flow. Usually, noise emitted by a vehicle such as a commercial vehicle is regulated by law, the noise being also referred to as noise emissions. Usually, commercial vehicles must be tested where wide open throttle acceleration at the beginning of a 100 foot track continues until rated or governed engine speed is reached within a 20 foot end section. For example, the maximum allowed sound level is 80 decibel (dBA) on either side of the vehicle. The engine is usually the primary noise source, and the results are highly correlated with maximum engine speed. By means of the air intake system according to the present invention, vehicle noise emission regulations can be met particularly efficiently.
Moreover, usually, a commercial vehicle such as a truck comprises a driver's cab configured to accommodate the driver of the vehicle. The air intake system according to the present invention not only reduces the exterior noise produced by a commercial vehicle such as a medium duty truck pertaining to the regulated limits specified, for example, in 40CFR205, but also attenuates noise within the driver's cab, particularly under hard acceleration. Moreover, a modest improvement in engine air intake water separation can also be achieved through a downturned pipe within the hood plenum.
Further advantages, features, and details of the invention derive from the following description of a preferred embodiment as well as from the drawings. The features and feature combinations previously mentioned in the description as well as the features and feature combinations mentioned in the following description of the figures and/or shown in the figures alone can be employed not only in the respectively indicated combination but also in other combination or taken alone without leaving the scope of the invention.